I have listed below a number of great sites for Math teachers. If you find a site not listed here that you think your colleagues will benefit from, email it to me and I will add it to the list. Comments, questions, suggestions - feel free to write me or stop me in the hall.
National Library of Virtual Manipulatives – Great interactive manipulatives to use on your whiteboard
Math Open Reference – A collection of mostly Geometry related resources
Statistics Through Application - the first text written exclusively for the non-AP, general level, introduction to statistics for high school students
Illuminations – A collection of lessons, activities, and links for Math teachers
Wolfram’s Math World – Animations and explanations for higher level math
Algebasics – Algebra Tutorial
CoolMath – as the site says ‘Designed for the pure enjoyment of mathematics
Paul’s Online Math Tutorial – by a university professor for his classes
Fun Math Lessons – some elementary, some HS
Problems with a Point – Math for grades 6 - 12
Nick’s Mathematical Puzzle’s - The math puzzles presented here are selected for the deceptive simplicity of their statement, or the elegance of their solution. They range over geometry, probability, number theory, algebra, calculus, trigonometry, and logic. All require a certain ingenuity, but usually only pre-college math.
Interactive Mathematics – Collection of Math resources
Fun Calculus Stuff – Tutorials and more, like Calculus Carols!
Geogebra - A great FREE tool similar to The Geometer’s Sketchpad
Fun Math Blog
Wilkes-Barre Schools District Math Wiki - A lot of great resources and ideas for your class.
Flash Card Creator
K-12 Math Forum from Drexel University
Online Math Activities - A large number of Math Activities for all levels.
Interactivate Online Math Activities - A great collection of interactive math demos.
Open Directory Project - A small collection of Java applets for Math and possibly Science.
Java Applets on Math - More Java dealing mainly with Geometry.
Manipula Math with Java - Yet another set of Java applets for Math.